The online method is done as follows:
Because all you need to do is capture and report the QC tax paid, here's what you will do:
First, use the option for "l worked in QC"
2nd: create a new T4 for with box 10 set to QC and enter the amount paid on the RL-2 as tax paid in the box E appearing at the bottom on the T4 with nothing else on the T4. Hence, nothing is reporting as a T4 to CRA:
By doing this, the QC tax will be reported and the rest of the entries are accurate.